Eucalypts in harare



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Fruits: sessile or on very short pedicels, ovoid to globular, 90-140 x 90-140 mm; rim thin; disc broad, descending; valves 3, deeply enclosed; seed red-brown, no wing.
Derivation of names: botanical - honours Count L de Torelli, member of Italian senate, who promoted use of eucalypts to dry up malarial Pontine Marshes near Rome; common - of Aboriginal origin.
Taxonomy: Subgenus Corymbia - woody-fruited bloodwoods.

Section Septentrionales - bark rough or smooth; leaves discolorous or concolorous; intramarginal vein present or absent; outer operculum usually persisting to flowering; seeds with or without a wing; of northern, central, and eastern Australian distribution, coastal, hills, and desert.

Subsection Aptera - seeds boat-shaped, unwinged; body of seed lustrous, reddish.

Series Torellianae - bark rough on lower part of trunk; outer operculum shed early.


Related species: the only species in the series, therefore no close relatives, but it shares characters with yellow blood-woods (Series Naviculares) and smooth-barked bloodwoods (Series Maculatae).
General: E. torelliana has a small natural distribution in coastal foothills and adjacent ranges of northern Queensland, north and south of Cairns; one of very few eucalypts that occur in tropical rain-forest. Unusual habitat, and green upper bark make it easy to identify. Hybridizes easily with E. citriodora in exotic environments, and would probably do so with E. maculata and E. henryi. Small plot of E. torelliana grows at Forest Research Centre, off Orange Grove Drive, Harare; one specimen in grounds of No 97 Harare Drive; a few trees at Hunyani Pulp Mill in Norton.

EUCALYPTUS CITRIODORA Hook. Lemon-scented gum
Habit: medium-sized to tall forest or woodland tree, usually well formed and of handsome appearance; bole usually half or more of tree height; crown of regular shape but sparsely foliaged.

Bark: usually smooth, white; coppery or pink in the north of the range; often spotted in the south; shedding in large curling flakes, with patches of blue-grey older attached bark.

Adult leaves: petiolate, alternate, lanceolate to narrow-lanceolate, 80-160 x 5-18 mm, green, concolorous, all with a strong smell of citronellal when crushed ( this includes dry fallen leaves beneath the tree); venation moderately conspic- uous, regular, at 35-50 degrees to midrib, intramarginal vein close to margin but distinct from it; densely reticulate,

numerous large oil glands.



Inflorescences: terminal corymbose panicles, 3-flowered; peduncles terete, 3-7 mm long; pedicels 1-6 mm long; buds club-shaped, 7-10 x 4-6 mm, no scar; operculum hemispherical-apiculate; flowers white, August-October.

Fruits: pedicellate, ovoid or urn-shaped, often warty, 7-15 x 7-11 mm; rim thin; disc broad, descending; valves 3-4, deeply enclosed; seed red-black.
Derivation of names: botanical - from Latin citron (lemon), and odor (smell); common - also from the strong lemon scent from the crushed leaves.
Taxonomy: Subgenus Corymbia - woody-fruited bloodwoods.

Section Septentrionales - (see E. torelliana).

Subsection Aptera - (see E. torelliana).

Series Maculatae - smooth-barked bloodwoods; bark smooth; outer operculum held until near flowering.


Related species: two other species, E. maculata and E. henryi, included in the series; although all three formerly included by Pryor and Johnson in Superspecies Maculata, relationship in Brooker's classification not quite so close; nearest relative E. maculata.
General: a Queensland endemic with a scattered distribution between latitudes 16 and 26 degrees S, occurring from coast to as much as 400 km inland, usually on dry ridges and uplands; an important commercial timber. Cultivated in Zimbabwe since about 1902, but never on any commercial scale; often disapp-ointing as a plantation species, but may be seen commonly along the country's main roads and in most towns. Perhaps the finest specimen in Harare stands in Hillside Park near the pedestrian gate at the intersection of Brooks Drive and Yates Road; it was probably planted in 1901-1903 and is now 50 m tall. The species is easily identifiable by its bark, and by the strong lemon scent of the crushed leaves.

EUCALYPTUS MACULATA Hook. Spotted gum
Habit: medium-sized to very tall forest tree with long clean bole to half or more of tree height; crown moderately open to dense.

Bark: smooth throughout, pink or blue-grey, thick, shed in more-or-less elliptical patches, leaving slight depressions in surface, differential weathering of these patches giving char-acteristic spotted appearance.

Adult leaves: petiolate, alternate, lanceolate to narrow-lanceolate, 120-210 x 12-30 mm, green, concolorous, slightly glossy; venation easily visible, at 35-50 degrees to midrib, regular but not closely parallel, intramarginal vein distinct; densely reticulate, numerous small oil glands.

Inflorescences: terminal corymbose panicles of 3-flowered (rarely 7) umbels; peduncles flattened or terete, 3-8 mm long; pedicels usually angular, 3-7 mm long; buds more or less ovoid, 6-10 x 4-6 mm, no scar; operculum hemispherical-apiculate or beaked; flowers white to cream, April-September.

Fruits: shortly pedicellate, barrel-shaped to slightly urn-shaped, 10-14 x 9-11 mm, woody; rim thin; disc broad, desc- ending; valves 3, deeply enclosed; seed red-black, lustrous.
Derivation of names: botanical - from Latin maculatus (spotted, blotched); common - from appearance of bark.
Taxonomy: Subgenus Corymbia - woody-fruited bloodwoods.

Section Septentrionales - (see E. torelliana).

Subsection Aptera - (see E. torelliana).

Series Maculatae - (see E. citriodora).


Related species: E. maculata falls between E. citriodora and E. henryi in Brooker's classification; in earlier draft of this work two subspecies listed, variegata and larseniana, but their present status not clear.
General: distribution is from Maryborough in Queensland south- wards through 13 degrees of latitude to southeastern Victoria. In north of range it occurs up to 400 km inland, but becomes progressively more coastal as range extends southwards; grows on clay and duplex soils; an important commercial timber tree. Believed to have been planted in Zimbabwe in 1892 by William Harvey Brown (1890 Pioneer and subsequently Mayor of Salisbury) at his farm Arlington, the site of present-day Harare International Airport, which would make it one of the earliest introductions of a eucalypt into the country. No actual specimens are known to me within Harare, but the species is bound to be present in the city or in the immediate environs.

EUCALYPTUS HENRYI S.T. Blake Large-leaved spotted gum
Habit: medium-sized to tall tree, very similar in general appearance to E. maculata.

Bark: smooth throughout, white to pale grey, pink, or cream, usually even in colour, shedding in small sheets or scales, and usually mottled.

Adult leaves: petiolate, alternate, lanceolate to narrow-lanceolate, 150-280 x 25-45 mm, thick (0.2-0.4 mm), green, concolorous, glossy or semi-glossy, acuminate; venation easily visible, coarse, more acute than in E. maculata, intramarginal vein distinct; oil glands abundant.

Inflorescences: terminal corymbose panicles, 3-flowered; peduncles 3-7 mm long; pedicels 2-4 mm long; buds ovoid, 9-13 x 6-8 mm, no scar; operculum hemispherical-apiculate or beaked; flowers white to cream, November-January.

Fruits: globoid or ovoid to urn-shaped, 11-20 x 10-16 mm, woody; rim thin; disc broad, descending; valves 3, deeply enclosed; seed red-brown, glossy.
Derivation of names: botanical - not known; common - from appearance of the bark, and larger leaves compared with

E. maculata.
Taxonomy: Subgenus Corymbia - woody-fruited bloodwoods.

Section Septentrionales - (see E. torelliana).

Subsection Aptera - (see E. torelliana).

Series Maculatae - (see E. citriodora); placed after



E. maculata in taxonomic listing.
Related species: closest relative is E. maculata, from which it differs in lack of, or fewer, peltate juvenile leaves, larger intermediate and adult leaves, larger buds, and larger fruit.
General: largely a coastal tree with a limited distribution from east of Toowoomba, Queensland, to Coffs Harbour, northern New South Wales; grows on soils derived from sandstone, as opposed to clay and duplex soils favoured by E. maculata. Formerly included in E. maculata, but described as separate species in 1976. Not known to have been introduced into Zimbabwe, but since it is very similar to E. maculata in appearance, it may be present but unrecognized. The natural range of E. henryi falls wholly within that of E. maculata, and seed is certain to have been collected and distributed outside Australia under the name of the longer-known species.

EUCALYPTUS GRANDIS Hill ex Maiden Flooded gum
Habit: tall to very tall forest tree, usually with clear straight bole to two-thirds or three-quarters of tree height; crown of mature trees spreading, rather open.

Bark: persistent rough "stocking" for 1-4 m, fibrous or flaking, grey to grey-brown; most of trunk and branches powdery white or grey-white, sometimes blue-grey, sometimes newly exposed bark pinkish.

Adult leaves: petiolate, alternate, lanceolate to broad- lanceolate, 100-160 x 20-30 mm, slightly wavy, with long point, discolorous, dark green above, paler below; venation fine, regular, parallel, at wide angle to midrib, intramarg- inal vein distinct; densely reticulate, oil glands obscure.

Inflorescences: axillary, simple, 7-flowered [some authors say 7-11]; peduncles flattened, 8-18 mm long; pedicels absent or up to 3 mm long, often stout and angular, tapering into base of bud; buds ovoid or pear-shaped, 5-8 x 3-4 mm, scar present; operculum conical or slightly beaked; flowers white, April-August.

Fruits: sessile or on very short pedicels, obconical or slightly pear-shaped, often glaucous, slightly contracted at rim, 5-8 x 4-7 mm; rim thin; disc obscure, descending, but may be narrow and more or less level; valves 4-5, exserted, broad, incurved; seed brown.
Derivation of names: botanical - directly from Latin, referring to large size commonly attained; common - refers to its preferred habitat in moist, but well-drained sites.
Taxonomy: Subgenus Symphyomyrtus.

Section Latoangulata [Transversaria in Pryor and Johnson classification] - valves of fruit prominent; cotyledons bilobed; leaves discolorous, entire, with wide-angled secondary veins, reticulation dense; inflorescences erect,

3->7-flowered; eastern Australian or extra-Australian.

Series Transversae - eastern blue gums - bark smooth over whole or upper half of trunk; ovules in 4 vertical rows; seeds flattened to shallowly pyramidal; hilum ventral.


Related species: series comprises 3 species only, E. deanei,

E. grandis, and E. saligna, latter two very closely related but not quite worthy of recognition at supraspecies level.

In earlier draft of classification Brooker listed E. grandis subsp kroombitensis, but present status of this not known.


General: distribution is along eastern seaboard of Australia from central New South Wales to southern Queensland, with smaller occurrences northwards into North Queensland. Not a prime timber species in Australia, but an extremely important plantation species in southern Africa and South America, covering millions of hectares and grown for pulpwood, poles, sawtimber, and charcoal. Common species in and around Harare, and on Zimbabwean highveld generally, but best development reached in warmer parts of Eastern Highlands. Heights up to 73 m recorded at Inodzi, near Penhalonga, and over 60 m at Felixburg, south of Mvuma, in rainfall zone of only 700 mm per annum. E. grandis not recognized in Australia as a species distinct from E. saligna until about 1923.

EUCALYPTUS SALIGNA Smith Sydney blue gum
Habit: medium-sized, tall, or very tall forest tree, usually with well-formed bole clear of branches for half or two-thirds of tree height.

Bark: brownish or greyish, rough, persistent at base up to

1-4 m, short-fibred, flaky, or often tessellated, decortic- cating in long strips to leave smooth bark on upper trunk and branches, which may be grey-green, bluish green, bluish grey, or white.



Adult leaves: petiolate, alternate, lanceolate, 90-170 x 20-30 mm, green, discolorous, hanging obliquely or tending to be horizontal; venation moderately fine, regular, at 35-55 deg- rees to midrib, intramarginal vein close to margin but distinct from it; densely reticulate,oil glands numerous.

Inflorescences: axillary, simple, 7-11-flowered; peduncles flattened, 4-18 mm long; pedicels absent or up to 3 mm long, angular, stout, often continuing into base of bud; buds ovoid, 6-9 x 3-4 mm, scar present; operculum conical or slightly beaked; flowers white, January-May.

Fruits: sessile or very shortly pedicellate, obconical to pear-shaped, sometimes cylindrical or bell-shaped, 5-8 x 4-7 mm; rim thin; disc narrow or obscure, descending; valves 3-4, with thin, pointed tips, protruding to just above rim level or strongly exserted, erect or curved strongly outwards; seed brown.
Derivation of names: botanical - from Latin salignus (willowy or willow-like), probably referring to long, often narrow leaves; common - refers to occurrence of species in Sydney region, and to sometimes bluish appearance of smooth bark.
Taxonomy: Subgenus Symphyomyrtus.

Section Latoangulata - (see E. grandis).



Series Transversae - eastern blue gums - (see E. grandis).
Related species: most closely related to E. grandis, less closely related to third member of series, E. deanei. In Pryor and Johnson classification E. saligna shown as being most closely related to E. botryoides, but now no longer believed to be so. Erect or outcurving valves of E. saligna most easily distinguish it from E. grandis, which has incurving valves. Seedling E. saligna can be distinguished from E. grandis by the presence in the former of lignotubers, and their absence in the latter.
General: mainly a species of the coastal regions of eastern Australia, from 21 degrees S in Queensland to 36 degrees S in New South Wales; range overlaps that of E. grandis, but

E. saligna always occupies cooler, drier sites. Possibly introduced into Zimbabwe as early as 1910; a small planting at Tilbury Estate, Chimanimani, dates from about this time, and some plantings in Nyanga National Park and Mtao Forest, near Mvuma, date from early 1920s. No specimens actually known in Harare, but species quite possibly does occur here, unrecognized among the commonly planted E. grandis.


EUCALYPTUS RESINIFERA Smith Red mahogany
Habit: medium-sized to tall forest tree, usually with clear straight bole up to half or two-thirds of tree height; crown well branched, compact, relatively dense.

Bark: greyish to reddish brown, rough, persistent throughout, thick, fibrous, fairly soft, with shallow, longitudinal fissures.

Adult leaves: petiolate, alternate, lanceolate to broad-lanceolate, often tapering off to long fine point, 100-170 x 18-35 mm, thick, discolorous, glossy dark green above, paler below, tending to be held horizontally; venation faint to moderately distinct, regular, at 45-60 degrees to midrib, intramarginal vein usually distinct; densely reticulate, oil glands numerous.

Inflorescences: axillary, simple, 7-11-flowered; peduncles flattened, 10-22 mm long; pedicels angular, 3-10 mm long; hypanthia ribbed, more or less hemispherical, overall bud size 12-20 x 5-6 mm, scar present; operculum acutely conical or horn-shaped, 1.5-3 times length of hypanthium; flowers white, June-August.

Fruits: strongly pedicellate, ovoid to hemispherical, 3-11 x 5-10 mm; rim thick; disc variable, usually slightly ascend- ing, but may be more or less level or descending; valves 3-4, strongly exserted, often turned outwards; seed brown.
Derivation of names: botanical - from Latin resina (resin), plus fera (bearing); not appropriate for this species, and is believed to have been applied due to an error involving a species of Subgenus Angophora; common - refers to red wood which early loggers thought similar to wood colour of Honduras mahogany, Swietenia mahagoni.
Taxonomy: Subgenus Symphyomyrtus.

Section Latoangulata - (see E. grandis).

Series Annulares - southern mahoganies - bark rough over whole trunk; ovules in 4-8 vertical rows; valves of fruit prominent; seeds pyramidal; hilum terminal.
Related species: series comprises 7 species: E. urophylla,

E. pellita, E. scias, E. notabilis (very closely related, but not quite to supraspecies level); E. resinifera, E. robusta, E. botryoides (very closely related, but not quite at supraspecies level). E. notabilis only species of this series not introduced into Zimbabwe.
General: distributed along eastern Australian coastal regions from 14 degrees S in Queensland to 35 degrees S in New South Wales, but large gaps occur in northern part of range; important timber in Australia. Introduced into Zimbabwe in 1920s; common at Mtao Forest, near Mvuma, and around Marondera, but no longer planted commercially. At one time commonly grown in nurseries in Harare, so quite possibly present as mature trees in city area, but no specimens known

to me.
EUCALYPTUS ROBUSTA Smith Swamp mahogany


Habit: small to medium-sized tree, usually with straight bole up to half of tree height; crown has long, spreading, irreg- ular branches carrying relatively dense canopy.

Bark: reddish grey-brown, rough, persistent to smaller branches, thick, held in coarse soft spongy elongated slabs, with deep longitudinal furrows.

Adult leaves: petiolate, alternate, broad-lanceolate, tapered to long fine point, 100-160 x 27-45 mm, strongly discolorous, dark glossy green above, pale green below, thick; venation fine, regular, more or less parallel, at 50-60 degrees to mid- rib, intramarginal vein usually distinct; densely reticulate, apparently glandless or oil glands obscure.

Inflorescences: simple, axillary, 9-15-flowered; peduncles strongly flattened, 13-30 mm long; pedicels 1-9 mm long, occasionally absent; buds with faintly ribbed obconical hypanthia, 16-24 x 6-8 mm, scar present; operculum long, beaked; flowers white, May-July.

Fruits: usually with prominent pedicels, cylindrical or con-stricted in middle, 10-18 x 6-11 mm; rim thick; disc broad, descending; valves 3-4, slightly below rim level or slightly exserted, tips usually joined together; seed brown.
Derivation of names: botanical - from Latin robustus (robust), but allusion obscure; common - refers to species' preference for swampy sites, and to similarity of wood colour to that of Honduras mahogany, Swietenia mahagoni.
Taxonomy: Subgenus Symphyomyrtus.

Section Latoangulata - (see E. grandis).



Series Annulares - (see E. resinifera).
Related species: closely related to both E. resinifera and

E. botryoides, less closely related to 4 other species in series (see under E. resinifera).
General: distributed along narrow coastal strip from southern Queensland to southern New South Wales; unusual for a eucalypt in growing on edges of saltwater estuaries and lagoons; wood of no great merit, not much used in Australia.

E. robusta introduced into Zimbabwe before 1902; particularly common in Chimanimani district, where it shows some signs of becoming naturalized (very unusual for a eucalypt); also encountered in unexpected places in Zimbabwe, and is quite possibly present in Harare, but no specimens known to me in city area. Consistently coherent valves are distinctive character of E. robusta; when it hybridizes with E. grandis, which it will do in Zimbabwe because of coincidence of flowering times, hybrid progeny usually have capsules and valves bearing strong resemblance to those of E. robusta.

EUCALYPTUS BOTRYOIDES Smith Southern mahogany
Habit: small to medium-sized woodland tree, or tall forest tree with dense crown, and, at its best, a well-formed bole extending to half or more of tree height.

Bark; grey to grey-brown, rough, persistent over whole trunk and often branches, thick, held in coarse slabs, with fairly conspicuous shallow longitudinal furrows; upper branches smooth, white or grey-white.

Adult leaves: petiolate, alternate, broad-lanceolate, often tapered to long fine point, 100-160 x 25-40 mm, strongly discolorous, glossy dark green above, paler below, thick, tending to be held horizontally; venation faint but usually visible, fairly regular, at 40-60 degrees to midrib, intra- marginal vein distinct from margin; densely reticulate.

Inflorescences: axillary, simple, 7-11-flowered; peduncles flattened, 7-15 mm long, broad; pedicels usually absent but occasionally up to 3 mm long, particularly for centre bud; buds cylindrical or club-shaped, often with ribbed hypanthia, up to 9 x 6 mm, scar present; operculum conical or hemi- spherical, much shorter than hypanthium, often with small rounded point; flowers white, December-February.

Fruits: sessile or with very short pedicels, cylindrical or barrel-shaped, 7-12 x 5-9 mm; rim thin; disc moderately broad, descending; valves 4, sometimes 3, up to rim level or slightly below; seed brown.
Derivation of names: botanical - from Greek botrys (cluster), possibly referring to buds and fruits; common - refers to its southerly latitudes compared with other mahoganies (mahogany, in context of eucalypts, refers to colour of red-brown wood which early Australian loggers regarded as similar to colour of Honduras mahogany, Swietenia mahagoni).
Taxonomy: Subgenus Symphyomyrtus.

Section Latoangulata - (see E. grandis).

Series Annulares - (see E. resinifera).
Related species: closely related to E. resinifera and

E. robusta, less closely related to 4 other species in series (see under E. resinifera). In Australia E. botryoides inter-grades with E. saligna where ranges overlap, even though relationship not close. E. botryoides easily distinguished from nearest relatives by its fruits and valves.
General: occurs naturally in very narrow coastal strip in southern New South Wales and southeastern Victoria; wood of good quality and used for general structural purposes. Introd-duced into Zimbabwe before 1902, known to have been planted within present-day city boundaries of Harare, but only one specimen currently known to me (at intersection of Wingate Road and Rhodesville Avenue); other specimens are almost certainly present elsewhere in Harare.

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